31287542 has 16 divisors (see below), whose sum is σ = 55136592. Its totient is φ = 13127520.

The previous prime is 31287541. The next prime is 31287559. The reversal of 31287542 is 24578213.

It is a junction number, because it is equal to n+sod(n) for n = 31287499 and 31287508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31287541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54413 + ... + 54984.

It is an arithmetic number, because the mean of its divisors is an integer number (3446037).

Almost surely, 2^31287542 is an apocalyptic number.

31287542 is a deficient number, since it is larger than the sum of its proper divisors (23849050).

31287542 is a wasteful number, since it uses less digits than its factorization.

31287542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109423.

The product of its digits is 13440, while the sum is 32.

The square root of 31287542 is about 5593.5267944294. The cubic root of 31287542 is about 315.1063452138.

The spelling of 31287542 in words is "thirty-one million, two hundred eighty-seven thousand, five hundred forty-two".